Value of tumor vessel sign in isolated circumscribed hypervascular abdominopelvic mesenchymal tumors on multidetector computed tomography.

OBJECTIVE: The objective was to determine the usefulness of the tumor vessel sign for differentiating the groups of circumscribed hypervascular abdominopelvic mesenchymal tumors. METHODS: We enrolled a total of 4 groups such as patients with gastrointestinal stromal tumor (GIST) (26 patients), those with paraganglioma (9 patients), those with primary sarcomas (13 patients, excluding those with liposarcoma), and those with desmoid tumor (6 patients). The reviewers evaluated the presence of tumor vessels capable of directly tracing from the tumor margin to the named vessels. RESULTS: Twenty-five of 26 GIST cases, all of the paragangliomas, all of the primary sarcomas, and all of the desmoid tumors showed a positive sign. For the sign confirming GIST, the sensitivity, specificity, positive and negative predictive values, and diagnostic accuracy were 96.2%, 100%, 100%, 96.6%, and 98.1%, respectively. The values of the area under the receiver operating characteristic curve have good or excellent diagnostic accuracies. CONCLUSIONS: The presence of the sign is considered to be helpful for differentiating the 4 groups of tumors.

Extragonadal sclerosing stromal tumor: a rare case report.

Sclerosing stromal tumor is a rare, benign, sex cord stromal tumor of the ovary. We report a case of extragonadal sclerosing stromal tumor in a 45-year-old woman who presented with menstrual irregularity and vague pelvic pain. Imaging studies showed a well-defined mass between the posterior wall of the bladder and uterus, suspected of being a pedunculated leiomyoma. The histopathological and immunohistochemical study was consistent with sclerosing stromal tumor. No ovarian tissue was found on representative sectioning. This is the first case of sclerosing stromal tumor in an extragonadal location.

Expression of hypoxia-inducible factor-1alpha and its relationship to tumour angiogenesis and cell proliferation in cartilage tumours.

We investigated the use of hypoxia-inducible factor (HIF) proteins as prognostic markers in chondrosarcoma and the relationship of HIF to the biological characteristics of cartilage tumours. The expression of HIF-1alpha, HIF-2alpha, proliferating cell nuclear antigen (PCNA) and microvessel density (MVD) were measured immunohistochemically in 29 specimens of cartilage tumour. There was no HIF-1alpha and HIF-2alpha staining in any of the nine benign cartilage tumours. In 20 specimens of chondrosarcoma, the rate of HIF-1alpha and HIF-2alpha expression was 40% and 25%, respectively. The tumour size (> or = 8 cm), histological grade (grade 2 and grade 3) surgical margin (marginal and intralesional) and HIF-1alpha expression (positive) correlated significantly with a shorter disease-free survival. There was a significant association between HIF-1alpha and the MVD and a strong trend towards a correlation between HIF-1alpha and the PCNA index or histological grade. Our findings suggest that HIF-1alpha protein may be a useful objective marker in the assessment of the prognosis in chondrosarcoma, since it plays an important role in tumour angiogenesis and cell proliferation.

Estimation of apparent tumor vascular permeability from multiphoton fluorescence microscopic images of P22 rat sarcomas in vivo.

OBJECTIVE: To develop an image processing-based method to quantify the rate of extravasation of fluorescent contrast agents from tumor microvessels, and to investigate the effect of the tumor vascular disrupting agent combretastatin A-4-P (CA-4-P) on apparent tumor vascular permeability to 40 kDa fluorescein isothiocyanate (FITC) labeled dextran. METHODS: Extravasation of FITC-dextran was imaged in 3 dimensions over time within P22 sarcomas growing in dorsal skin flap "window chambers" in BDIX rats using multiphoton fluorescence microscopy. Image processing techniques were used to segment the data into intra- and extravascular regions or classes. Quantitative estimates of the tissue influx (vascular leakage) rate constant, K(i), were obtained from the time courses of the fluorescence intensities in the two classes. Apparent permeability, P, was calculated, assuming K(i) = PS/V, where S is vascular surface area in tumor volume V. RESULTS: Combining image processing and kinetic analysis algorithms with multiphoton fluorescence microscopy enabled quantification of the rate of tumor vascular leakage, averaged over a large number of vessels. Treatment with CA-4-P caused a significant increase in K(i) from 1.13 +/- 0.33 to 2.59 +/- 0.20 (s(- 1)x 10(- 4); mean +/- SEM), equivalent to an increase in P from 12.76 +/- 3.36 to 30.94 +/- 2.64 (cm s(-1)x 10(-7)). CONCLUSIONS: A methodology was developed that provided evidence for a CA-4-P-induced increase in tumor macromolecular vascular permeability, likely to be central to its anti-cancer activity.